<template>
  <transition name="list-fade">
    <div
      class="playlist"
      v-show="showFlag"
      @click="hide"
    >
      <div
        class="list-wrapper"
        @click.stop
      >
        <div class="list-header">
          <h1 class="title">
            <i
              class="icon"
              :class="iconMode"
              @click="changeMode"
            ></i>
            <span class="text">{{ modeText }}</span>
            <span
              class="clear"
              @click="showConfirm"
            >
              <i class="icon-clear"></i>
            </span>
          </h1>
        </div>
        <scroll
          :refreshDelay="refreshDelay"
          :data="sequenceList"
          class="list-content"
          ref="listContent"
        >
          <transition-group
            ref="list"
            name="list"
            tag="ul"
          >
            <li
              ref="listItem"
              class="item"
              v-for="(item, index) in sequenceList"
              :key="item.id"
              @click="selectItem(item, index)"
            >
              <i
                class="current"
                :class="getCurrentIcon(item)"
              ></i>
              <span class="text">{{ item.name }}</span>
              <span
                class="like"
                @click.stop="toggleFavorite(item)"
              >
                <i :class="getFavoriteIcon(item)"></i>
              </span>
              <span
                class="delete"
                @click.stop="deleteOne(item)"
              >
                <i class="icon-delete"></i>
              </span>
            </li>
          </transition-group>
        </scroll>
        <div class="list-operate">
          <div
            class="add"
            @click="addSong"
          >
            <i class="icon-add"></i>
            <span class="text">添加歌曲到队列</span>
          </div>
        </div>
        <div
          class="list-close"
          @click="hide"
        >
          <span>关闭</span>
        </div>
      </div>
      <confirm
        text="是否清空播放列表"
        confirmBtnText="清空"
        ref="confirm"
        @confirm="confirmClear"
      ></confirm>
      <add-song ref="addSong"></add-song>
    </div>
  </transition>
</template>

<script type='text/ecmascript-6'>
import { mapActions } from 'vuex'
import { playMode } from 'common/js/config'
import Scroll from 'base/scroll/scroll'
import Confirm from 'base/confirm/confirm'
import { playerMixin } from 'common/js/mixin'
import AddSong from 'components/add-song/add-song'

export default {
  mixins: [playerMixin],
  data() {
    return {
      showFlag: false,
      refreshDelay: 100
    }
  },
  computed: {
    modeText() {
      return this.mode === playMode.sequence
        ? '顺序播放'
        : this.mode === playMode.random
          ? '随机播放'
          : '单曲循环'
    }
  },
  methods: {
    show() {
      this.showFlag = true
      setTimeout(() => {
        this.$refs.listContent.refresh()
        this.scrollToCurrent(this.currentSong)
      }, 20)
    },
    hide() {
      this.showFlag = false
    },
    getCurrentIcon(item) {
      return item.id === this.currentSong.id ? 'icon-play' : ''
    },
    selectItem(item, index) {
      if (this.mode === playMode.random) {
        index = this.playlist.findIndex((song) => {
          return song.id === item.id
        })
      }
      this.setCurrentIndex(index)
      this.setPlayingState(true)
    },
    scrollToCurrent(current) {
      const index = this.sequenceList.findIndex((song) => {
        return current.id === song.id
      })
      this.$refs.listContent.scrollToElement(this.$refs.list.$el.children[index], 300)
    },
    deleteOne(item) {
      this.deleteSong(item)
      if (!this.playlist.length) {
        this.hide()
      }
    },
    showConfirm() {
      this.$refs.confirm.show()
    },
    confirmClear() {
      this.deleteSongList()
      this.hide()
    },
    addSong() {
      this.$refs.addSong.show()
    },
    ...mapActions([
      'deleteSong',
      'deleteSongList'
    ])
  },
  watch: {
    currentSong(newSong, oldSong) {
      // 如果该组件没有显示,并且新歌和旧歌相同,就return
      if (!this.showFlag || newSong.id === oldSong.id) {
        return
      }
      setTimeout(() => {
        this.scrollToCurrent(newSong)
      }, 20)
    }
  },
  components: {
    Scroll,
    Confirm,
    AddSong
  }
}
</script>

<style scoped lang='stylus' rel='stylesheet/stylus'>
@import '~common/stylus/variable'
@import '~common/stylus/mixin'

.playlist
  position: fixed
  left: 0
  right: 0
  top: 0
  bottom: 0
  z-index: 200
  background-color: $color-background-d
  &.list-fade-enter-active, &.list-fade-leave-active
    transition: opacity 0.3s
    .list-wrapper
      transition: all 0.3s
  &.list-fade-enter, &.list-fade-leave-to
    opacity: 0
    .list-wrapper
      transform: translate3d(0, 100%, 0)
  &.list-fade-enter, .list-wrapper
    position: absolute
    left: 0
    bottom: 0
    width: 100%
    background-color: $color-highlight-background
    .list-header
      position: relative
      padding: 20px 30px 10px 20px
      .title
        display: flex
        align-items: center
        .icon
          margin-right: 10px
          font-size: 30px
          color: $color-theme-d
        .text
          flex: 1
          font-size: $font-size-medium
          color: $color-text-l
        .clear
          extend-click()
          .icon-clear
            font-size: $font-size-medium
            color: $color-text-d
    .list-content
      max-height: 240px
      overflow: hidden
      .item
        display: flex
        align-items: center
        height: 40px
        padding: 0 30px 0 20px
        overflow: hidden
        &.list-enter-active, &.list-leave-active
          transition: all 0.1s linear
        &.list-enter, &.list-leave-to
          height: 0
        .current
          flex: 0 0 20px
          width: 20px
          font-size: $font-size-small
          color: $color-theme-d
        .text
          flex: 1
          no-wrap()
          font-size: $font-size-medium
          color: $color-text-d
        .like
          extend-click()
          margin-right: 15px
          font-size: $font-size-small
          color: $color-theme
          .icon-favorite
            color: $color-sub-theme
        .delete
          extend-click()
          font-size: $font-size-small
          color: $color-theme
    .list-operate
      width: 140px
      margin: 20px auto 30px auto
      .add
        display: flex
        align-items: center
        padding: 8px 16px
        border: 1px solid $color-text-l
        border-radius: 100px
        color: $color-text-l
        .icon-add
          margin-right: 5px
          font-size: $font-size-small-s
        .text
          font-size: $font-size-small
    .list-close
      text-align: center
      line-height: 50px
      background: $color-background
      font-size: $font-size-medium-x
      color: $color-text-l
</style>
